LIFE-HISTORY OF THE COHO 45 
SESSIONAL PAPER No. 38a 
WEIGHT. 
Length. NANAIMO. Neau Bay. 
Male. Female. Male. Female. 
In Lbs Lbs. Lbs Lbs 
SE aN rhe icteca le A Raia es ads sky ona scake choke aR, eee Ale See 3-75 3°75 
Se heal Pa lees rail (ssh one, ele 
(NO gh Ak A ee ea ae 
PERS Serta MM NS rel: = Soars a aM ey cl ahs Sued acer 4 GIR cease rete te lle Rheem be Docs |b secre 
Mee Llanes Ge alist oat 
4-625 4-75 5-5 
4-875 RAEI ears tr arthiek ale 
5-25 itr diy ballSe co aiiG see 
5-5 5-75 6-5 5-75 
5-875 ong! Teenie its 7-5 
6-375 Gos 7Dillas pee 7:5 
6-5 6-75 7-25 8-5 
6-625 7: 7-5 8- 
7: 7-25 8- 8-25 
8- Sie Gs eet eee 10-25 
8-25 8-375 9- 9-25 
g- 9-25 9-5 10- 
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5 rh Sick ADIGA ELD Ry ke SoM A a et IB, Se mea 10: 11-5 11-5 
9-75 11-5 11-5 11-75 
oobi filedvers Socket 12- 12- 
Fe aR | cr oe a RPT Oe 12-75 15 
ahs, Lael lps CANALES 13- 13- 
Si 7:0) haha | MRI sks oi [Rie cee eran 
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STS ANS 6 Pee ae acer RAR ee ce 
SUMMARY. 
The coho, which is mature in its third year, spends the entire first year, with 
but very few exceptions, in the Vancouver Island region, in the fresh water. Some 
of them migrate about the time the first year is completed, but others remain later, 
even until well on in the summer. There is no indication that any remain in fresh 
water to complete the second year. The scale shows a distinct winter check in the 
fresh water growth and another in the sea growth. 
The average length is 3-3 inches at the end of the first year, 14-3 inches at the 
end of the second year, and 24,-0 inches when caught in the fall of the third year. 
There is an indication that the fish that are largest at the end of the first year 
become the largest mature fish. Although some of the yearlings stay in the fresh 
water longer than others, it was not apparent that this made any special difference 
in the ultimate size of the fish. 
There is a definite ratio between length and weight. In the mature fish, the 
females weigh slightly more than the males of the same length. 
In connection with artificial propagation, as large a portion as possible for the 
season’s hatching should be procured from the early spawning fish that the fry may 
be larger at the end of the first year and consequently larger as mature fish. 
No species of Pacific salmon should get more benefit from rearing ponds than 
the coho, as almost the whole of the fry remain in the fresh water for a year in any 
case, and very few naturally get the benefit of accelerated growth in the salt water 
in the first year. 
From the standpoint of economy, the waste caused by early fishing can readily 
be appreciated when the great percentage increase in weight during the summer 
months of the third year is taken into account. 
